#define _GNU_SOURCE

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/wait.h>
#include <string.h>
#include <signal.h>
#include <errno.h>
#include <setjmp.h>
#include "readcmd.h"
#include "jobs.h"

int prompting = 0;
int job_id = 1;
list jobs;

void handler_print(int signal_num, siginfo_t* info) {
  if (contiens(&jobs, info->si_pid)) {
    if (prompting) { printf("\n"); }
    printf("[%d] --> (%d) %s\n", info->si_pid, signal_num, strsignal(signal_num));
    supprimer(&jobs, info->si_pid);
    job_id--;
  }
}

int main(int argc, char *argv[]) {

  extern int errno;
  
  initialiser(&jobs);

  struct sigaction action;
  action.sa_flags = SA_SIGINFO; //| SA_RESTART;
  action.sa_handler = handler_print;
  sigemptyset(&action.sa_mask);
  sigaction(SIGCHLD, &action, NULL);


  char initcd[256], currentcd[256];
  getcwd(initcd, 256);

  while (1) {
    getcwd(currentcd, 256);
    printf("%s >>> ", currentcd);
    prompting = 1;
    struct cmdline* cmd = readcmd();
    prompting = 0;

    if (cmd == NULL || cmd->seq[0] == NULL) { // ligne vide, on skip
      continue;
    } else if (!strcmp(cmd->seq[0][0], "exit")) { // on quitte le shell
      break;
    } else if (!strcmp(cmd->seq[0][0], "cd")) { // cd
      if (cmd->seq[0][1] == NULL) { // vide
        chdir(initcd);
      } else { // avec un path
        chdir(cmd->seq[0][1]);
      }
      continue;
    } else if (!strcmp(cmd->seq[0][0], "jobs")) {
      afficher(&jobs);
      continue;
    }

    pid_t pidFils = fork();

    if (pidFils == -1) {
      fprintf(stderr, "ERROR: forking failed, %s\n", strerror(errno));
      exit(errno);
    }

    if (pidFils == 0) { // fils
      execvp(cmd->seq[0][0], cmd->seq[0]);
      exit(errno); // si execlp échoue on exit avec une erreur

    } else { // père
      if (cmd->backgrounded) {
        ajouter(&jobs, pidFils, job_id++);      
      } else {
        jmp_buf env;
        setjmp(env);
        int codeTerm;
        pid_t idFils = waitpid(pidFils, &codeTerm, 0); // on attend la fin de l'exec du fils

        if (idFils == -1){

          // todo : peut mieux faire ?
          if (errno == 4) {
            longjmp(env, 1);
          }

          fprintf(stderr, "ERROR: waiting for %d failed, (%d) %s\n", codeTerm, errno, strerror(errno));
          exit(errno);
        }

      }
    }
  }

  return EXIT_SUCCESS;
}